use std::path::Path;

#[cfg(feature = "cuda")]
use cudarc::driver::CudaDevice;

#[cfg(feature = "metal")]
use metal_rs::{Device, CommandQueue};

#[derive(Debug)]
pub enum AccelerationBackend {
    #[cfg(feature = "cuda")]
    CUDA(CudaDevice),
    #[cfg(feature = "metal")]
    Metal(Device, CommandQueue),
    CPU,
}

#[derive(Debug)]
pub struct Model {
    // 模型数据结构
}

pub type InferenceResult = Result<(), String>;

#[derive(Debug)]
pub enum AccelerationError {
    CudaError(String),
    MetalError(String),
    CpuError(String),
}

impl AccelerationBackend {
    pub fn auto_select() -> Self {
        #[cfg(feature = "cuda")]
        if let Ok(device) = CudaDevice::new(0) {
            return Self::CUDA(device);
        }
        
        #[cfg(feature = "metal")]
        if let Some(device) = Device::system_default() {
            let queue = device.new_command_queue();
            return Self::Metal(device, queue);
        }

        Self::CPU
    }

    pub fn run_model(&self, model: &Model) -> Result<InferenceResult, AccelerationError> {
        match self {
            #[cfg(feature = "cuda")]
            Self::CUDA(dev) => self.run_cuda(dev, model),
            #[cfg(feature = "metal")]
            Self::Metal(dev, queue) => self.run_metal(dev, queue, model),
            Self::CPU => self.run_cpu(model),
        }
    }

    #[cfg(feature = "cuda")]
    fn run_cuda(&self, device: &CudaDevice, model: &Model) -> Result<InferenceResult, AccelerationError> {
        // CUDA 实现
        Ok(Ok(()))
    }

    #[cfg(feature = "metal")]
    fn run_metal(&self, device: &Device, queue: &CommandQueue, model: &Model) -> Result<InferenceResult, AccelerationError> {
        // Metal 实现
        Ok(Ok(()))
    }

    fn run_cpu(&self, model: &Model) -> Result<InferenceResult, AccelerationError> {
        // CPU 实现
        Ok(Ok(()))
    }
}